TEST Bank AQA A Level Biology Questions
and Answers | 100% Correct | A+ Verified |
2026
• how to killer t-cells work? -✓✓1. virus attaches to and enters host cell
2. viral DNA causes host cell to express viral antigens on its surface
3. killer t-cells attaches to viral antigens on infected cells
4. killer t-cells induces death of infected cell (apoptosis)
• what is apoptosis? -✓✓programmed cell death
• how do killer t-cells destroy cancer? -✓✓- cancerous = mutations
- mutations = abnormal antigens
- killer t-cell binds to abnormal antigens
- killer t-cells induces death of cancerous cell
• What does perforin do? -✓✓creates holes in the cell membranes in order to destroy
the infected cell
• what do helper t-cells do? -✓✓- produce cytokines
- cytokines stimulate b-cells to divide into plasma and memory cells
- activate killer t-cells
• define helper t-cells -✓✓help humoral response by involvement in the maturation of b-
cells and by triggering the production of antibodies by b-cells
• what do suppressor t-cells do? -✓✓- halt immune response
- prevent wastage of energy and resources
- prevent overactive immune response
- causes reduction of white blood cells after being ill
• define memory t-cells -✓✓work in the same way as memory b-cells, ensuring rapid
response on subsequent exposure to the same non-self antigens
• define suppressor t-cells -✓✓regulate the immune response by suppressing activity of
killer t-cells and b-cells
• define 'microorganism' -✓✓organism that is too small to be seen without a microscope
• define 'pathogen' -✓✓microorganism that causes disease
• outline phagocytosis -✓✓1. phagocyte follows conc gradient of chemoattractants
2. phagocyte attaches to pathogen
,3. pathogen engulfed and placed in a vesicle (phagosome)
4. lysosomes migrate to phagosome and bind with it to form a phagolysosome
--> lytic enzymes released from lysosome
5. pathogen digested
6. useful parts absorbed
7. all waste products released by exocytosis
8. non-self antigens of the pathogen displayed on the phagocytes surface (antigen-
presenting)
• where are t-cells made? -✓✓thymus gland
• where do b-cells mature? -✓✓bone marrow
• what do b-cells do? -✓✓- humoral response
- release antibodies
- complementary to a specific antigen
• what response are plasma cells? -✓✓primary
• what response are memory b-cells? -✓✓secondary
• outline the humoral response -✓✓1. antigen attaches to complementary antibody on b-
cell
2. antigen taken into cell (endocytosis)
3. presented on cell surface membrane
4. t-helper cells bind to antigen and stimulate b-cell to divide
• what does mitosis do in humoral response? -✓✓- forms clones of b-cells (plasma and
memory)
- clonal response
• what do clones do? -✓✓each clone can produce one type of antibody (monoclonal)
which can be used in medicine
• outline plasma cells -✓✓- primary response
- secrete antibodies
- only survive for a few day
- slow response = person gets ill before pathogen is killed
• outline memory cells -✓✓- secondary response
- circulated in blood and tissue fluid
- divide rapidly
- rapid response so person doesn't get ill
• what is an antibody? -✓✓y-shaped globular protein produced by b-cells
,• where are antibodies produced? -✓✓plasma b-cells
• what are antibodies made of? -✓✓4 polypeptide chains -- 2 heavy, 2 light
• what are the two regions an antigen is made of? -✓✓- variable
- constant
• what is special about the variable region? -✓✓complementary and specific to an
antigen
• what are the chains bonded by? -✓✓disulphide bridge
• why do antibodies have a hinge region? -✓✓to allow the antibody to move to bind to
more than one antigen
• what is 'monoclonal antibody production' -✓✓the process by which large quantities of
antibodies (targeted against a particular antigen) can be produced
• how are monoclonal antibodies produced? -✓✓- mouse immunised by injection of
antigen to stimulate production of antibodies
- plasma cells isolated from spleen
- plasma cells fuse with tumor cells to form a hybridoma
- hybridoma produces large amounts of identical antibody molecules
• what is the scientific term for a tumor cell? -✓✓myeloma
• what can be monoclonal antibodies be used as? -✓✓specific probe to track down and
purify specific protein that induced its transformation
• what needs to happen to monoclonal antibodies before human use? -✓✓humanisation
• why do monoclonal antibodies need to be 'humanised' before used by humans? -✓✓to
stop the trigger of an immune response
• what are monoclonal antibodies used for? -✓✓- pregnancy tests
- diagnostic tools for AIDS
- industrial production of interferon
• what is a vaccine? -✓✓a dead or weakened version of a disease with relevant
antigens
• what is a vaccination? -✓✓introduction of a vaccine containing appropriate disease
antigens into the body to induce artificial immunity
, • how do vaccines work? -✓✓- pathogen stimulaties wbc into making antigens
- dead or inactive pathogen enter body via injection
- antibodies stick to antigens and clump them together
- memory cells = immunity
• what are the pros of immunisation? -✓✓- protected from certain diseases
- economic benefits
- eradicate diseases
- prevent epidemics
• what are the cons of immunisation? -✓✓- chance of contracting diseases from vaccine
- religions might be against it
- side effects
- only work for a certain amount of time
- antigenic variability
- certain pathogens hide from immune system
• what is HIV -✓✓a retrovirus that attacks the body's immune system
• what are the modes of transmission of HIV -✓✓- blood (transfusions)
- sharing needles
- breast feeding/ giving birth
- sex
• what is herd immunity'? -✓✓vaccinating enough people so there isn't enough hosts for
the virus to spread
• define 'epidemic' -✓✓infection of a country
• define 'endemic' -✓✓infection of a specific area
• define 'pandemic' -✓✓infection of more than one country
• give 2 types of natural immunity -✓✓- infection
- maternal antibodies
• give 2 types of artificial immunity -✓✓- vaccine
- monoclonal antibodies
• how does HIV result in the death of a t-cell? -✓✓- HIV recognises helper t-cell
- apoptosis
and Answers | 100% Correct | A+ Verified |
2026
• how to killer t-cells work? -✓✓1. virus attaches to and enters host cell
2. viral DNA causes host cell to express viral antigens on its surface
3. killer t-cells attaches to viral antigens on infected cells
4. killer t-cells induces death of infected cell (apoptosis)
• what is apoptosis? -✓✓programmed cell death
• how do killer t-cells destroy cancer? -✓✓- cancerous = mutations
- mutations = abnormal antigens
- killer t-cell binds to abnormal antigens
- killer t-cells induces death of cancerous cell
• What does perforin do? -✓✓creates holes in the cell membranes in order to destroy
the infected cell
• what do helper t-cells do? -✓✓- produce cytokines
- cytokines stimulate b-cells to divide into plasma and memory cells
- activate killer t-cells
• define helper t-cells -✓✓help humoral response by involvement in the maturation of b-
cells and by triggering the production of antibodies by b-cells
• what do suppressor t-cells do? -✓✓- halt immune response
- prevent wastage of energy and resources
- prevent overactive immune response
- causes reduction of white blood cells after being ill
• define memory t-cells -✓✓work in the same way as memory b-cells, ensuring rapid
response on subsequent exposure to the same non-self antigens
• define suppressor t-cells -✓✓regulate the immune response by suppressing activity of
killer t-cells and b-cells
• define 'microorganism' -✓✓organism that is too small to be seen without a microscope
• define 'pathogen' -✓✓microorganism that causes disease
• outline phagocytosis -✓✓1. phagocyte follows conc gradient of chemoattractants
2. phagocyte attaches to pathogen
,3. pathogen engulfed and placed in a vesicle (phagosome)
4. lysosomes migrate to phagosome and bind with it to form a phagolysosome
--> lytic enzymes released from lysosome
5. pathogen digested
6. useful parts absorbed
7. all waste products released by exocytosis
8. non-self antigens of the pathogen displayed on the phagocytes surface (antigen-
presenting)
• where are t-cells made? -✓✓thymus gland
• where do b-cells mature? -✓✓bone marrow
• what do b-cells do? -✓✓- humoral response
- release antibodies
- complementary to a specific antigen
• what response are plasma cells? -✓✓primary
• what response are memory b-cells? -✓✓secondary
• outline the humoral response -✓✓1. antigen attaches to complementary antibody on b-
cell
2. antigen taken into cell (endocytosis)
3. presented on cell surface membrane
4. t-helper cells bind to antigen and stimulate b-cell to divide
• what does mitosis do in humoral response? -✓✓- forms clones of b-cells (plasma and
memory)
- clonal response
• what do clones do? -✓✓each clone can produce one type of antibody (monoclonal)
which can be used in medicine
• outline plasma cells -✓✓- primary response
- secrete antibodies
- only survive for a few day
- slow response = person gets ill before pathogen is killed
• outline memory cells -✓✓- secondary response
- circulated in blood and tissue fluid
- divide rapidly
- rapid response so person doesn't get ill
• what is an antibody? -✓✓y-shaped globular protein produced by b-cells
,• where are antibodies produced? -✓✓plasma b-cells
• what are antibodies made of? -✓✓4 polypeptide chains -- 2 heavy, 2 light
• what are the two regions an antigen is made of? -✓✓- variable
- constant
• what is special about the variable region? -✓✓complementary and specific to an
antigen
• what are the chains bonded by? -✓✓disulphide bridge
• why do antibodies have a hinge region? -✓✓to allow the antibody to move to bind to
more than one antigen
• what is 'monoclonal antibody production' -✓✓the process by which large quantities of
antibodies (targeted against a particular antigen) can be produced
• how are monoclonal antibodies produced? -✓✓- mouse immunised by injection of
antigen to stimulate production of antibodies
- plasma cells isolated from spleen
- plasma cells fuse with tumor cells to form a hybridoma
- hybridoma produces large amounts of identical antibody molecules
• what is the scientific term for a tumor cell? -✓✓myeloma
• what can be monoclonal antibodies be used as? -✓✓specific probe to track down and
purify specific protein that induced its transformation
• what needs to happen to monoclonal antibodies before human use? -✓✓humanisation
• why do monoclonal antibodies need to be 'humanised' before used by humans? -✓✓to
stop the trigger of an immune response
• what are monoclonal antibodies used for? -✓✓- pregnancy tests
- diagnostic tools for AIDS
- industrial production of interferon
• what is a vaccine? -✓✓a dead or weakened version of a disease with relevant
antigens
• what is a vaccination? -✓✓introduction of a vaccine containing appropriate disease
antigens into the body to induce artificial immunity
, • how do vaccines work? -✓✓- pathogen stimulaties wbc into making antigens
- dead or inactive pathogen enter body via injection
- antibodies stick to antigens and clump them together
- memory cells = immunity
• what are the pros of immunisation? -✓✓- protected from certain diseases
- economic benefits
- eradicate diseases
- prevent epidemics
• what are the cons of immunisation? -✓✓- chance of contracting diseases from vaccine
- religions might be against it
- side effects
- only work for a certain amount of time
- antigenic variability
- certain pathogens hide from immune system
• what is HIV -✓✓a retrovirus that attacks the body's immune system
• what are the modes of transmission of HIV -✓✓- blood (transfusions)
- sharing needles
- breast feeding/ giving birth
- sex
• what is herd immunity'? -✓✓vaccinating enough people so there isn't enough hosts for
the virus to spread
• define 'epidemic' -✓✓infection of a country
• define 'endemic' -✓✓infection of a specific area
• define 'pandemic' -✓✓infection of more than one country
• give 2 types of natural immunity -✓✓- infection
- maternal antibodies
• give 2 types of artificial immunity -✓✓- vaccine
- monoclonal antibodies
• how does HIV result in the death of a t-cell? -✓✓- HIV recognises helper t-cell
- apoptosis
